Drivers are circuits used for signal communication, either between integrated circuits (“ICs”) or within a single IC. By way of example and not limitation, drivers can be used to communicate signals, such as to transmit data signals to and from a memory, or to transmit control signals to and from a memory controller.
A “differential” output driver receives substantially concurrently two input signals and generates substantially concurrently two output signals. Information is typically conveyed by the potential difference between the two output signals. One output signal typically has a potential substantially equal to a first supply voltage (e.g., VCC) and the other output signal typically has a potential substantially equal to a second supply voltage (e.g., VSS, which may be, for example, a negative voltage or ground). Such pairs of signals are known as differential signals. Differential output drivers are relatively immune to noise and jitter, because any noise or jitter that affects the voltage of one output signal will often affect in substantially the same way the voltage of the other output signal.
A serialization function of a serializer/deserializer (SerDes) converts parallel signals (e.g., data signals) to a serial signal(s) (e.g., in preparation for transmitting the serial data), and the deserialization function of the SerDes converts a received serial signal(s) to parallel signals. A SerDes can take a wide bit-width parallel bus and output differential signals that switch at a much higher frequency rate than the parallel bus. The communication (e.g., transmission) of signals over a high speed serial communication path rather than slower parallel communication paths enable the movement of a large amount of data point-to-point while reducing complexity, cost, power, and space requirements. Thus, a SerDes may achieve high data throughput while lowering power requirements and integrated circuit area.